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    Data Transfer over long twisted pair cable

    Hi Guys,

    I need to have a high rate data transfer of about 10Mbps on a twisted-pair wired line over a long distance of about 1500 meters.

    From my searches, I came to the conclusion that over the long haul, protocols like the RS485 did not meet my needs.
    I think I should use parts that do some sort of signal modulation and demodulation themselves.

    Can anyone introduce components or modules to do this?

    so thanks.

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    Re: Data Transfer over long rwisted pair cable

    you might consider this, from the CRC Handbook of Modern Telecommunications

    https://books.google.com/books?id=gj...20meter&f=true

    paragraph 1.4.2.6.5 10BaseFL
    fiber optics up to 2000 meters



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    Re: Data Transfer over long rwisted pair cable

    ADSL hardware seems to be perfect for this:
    https://en.wikipedia.org/wiki/Asymme...ubscriber_line



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    Re: Data Transfer over long rwisted pair cable

    I'm going to use FPGA or eventually ARM to control the chip.
    Has anyone had the experience of running ADSL / VDSL chips with FPGA or ARMs? And can anybody introduce a chip that doesn't have the complexity of a startup?



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    Re: Data Transfer over long twisted pair cable

    Quote Originally Posted by Port Map View Post
    Hi Guys,

    I need to have a high rate data transfer of about 10Mbps on a twisted-pair wired line over a long distance of about 1500 meters.

    From my searches, I came to the conclusion that over the long haul, protocols like the RS485 did not meet my needs.
    I think I should use parts that do some sort of signal modulation and demodulation themselves.

    Can anyone introduce components or modules to do this?

    so thanks.
    Hello,

    what about "CAN FD" (the newest CAN standard). It has max. data transfer rate close to your requirements (8Mbps). I am using "CAN FD" in my newest project based on STM32MP157A MCU and it is working fine so far. Earlier I had been using CAN 2.0. "CAN FD" has higher speed comparing to CAN 2.0B standard and also longer frame - up to 64 byte versus 8 byte . And it is relatively simple in use.

    Regards

    BTW: second alternative could be some kind of "TCP/IP" protocol over twisted pair - what was mentioned by coleagues in posts above ;)
    Last edited by FlyingDutch; 30th October 2019 at 15:41.



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    Re: Data Transfer over long twisted pair cable

    Quote Originally Posted by FlyingDutch View Post
    Hello,

    what about "CAN FD" (the newest CAN standard). It has max. data transfer rate close to your requirements (8Mbps). I am using "CAN FD" in my newest project based on STM32MP157A MCU and it is working fine so far. Earlier I had been using CAN 2.0. "CAN FD" has higher speed comparing to CAN 2.0B standard and also longer frame - up to 64 byte versus 8 byte . And it is relatively simple in use.

    Regards

    BTW: second alternative could be some kind of "TCP/IP" protocol over twisted pair - what was mentioned by coleagues in posts above ;)
    "CAN FD" is specified for 10 meters maximum distance, the requirement here is 1500 meters. Also, the expected average bit rate is probably below 4 Mbit/s:
    https://www.computer-solutions.co.uk...n_tutorial.htm

    "TCP/IP" is a (software) protocol, and has nothing to do with transferring bits on the physical layer (the twisted pair).

    The requirement in this thread is very similar to what was wanted to replace dial-up modems for accessing internet. The solution was ADSL, and I doubt that there is a better/cheaper way to do it on a twisted pair.
    The alternative is probably some kind of wireless link, which may require a free line-of-sight.



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    Re: Data Transfer over long rwisted pair cable

    The RS-422 / RS-485 cable plant has a bit rate * distance
    product in the specs. Whether you can "overclock" it is
    going to depend on intersymbol interference, probably
    not pretty.

    What about fiber optics? Pluggable FO transceiver modules
    using 4-fiber standard(-ish) flat cables are a thing now.
    You won't want for bandwidth, that's for sure. No EMI
    issues neither.



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    Re: Data Transfer over long rwisted pair cable

    Hi,

    What about RS422/RS485 with repeater/driver?
    You may use a pair as power supply for the drivers.

    Klaus
    Please donīt contact me via PM, because there is no time to respond to them. No friend requests. Thank you.



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    Re: Data Transfer over long rwisted pair cable

    Seems like 485 can do the distance at reduced rate. Make it up with additional twisted pairs?



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    Re: Data Transfer over long twisted pair cable

    Can anyone introduce components or modules to do this?
    Have you considered the venerable current loop? It is a serial protocol but was widely used in good old days - but I am not so sure about the speed.



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    Re: Data Transfer over long rwisted pair cable

    Neither bit rate nor length can be reduced. I need 10Mbps at 1500 meters.

    I realized that VDSL is a good solution for my needs, Manufacturers like "Metanoia" have products in the field, but I haven't been able to find parts with complete datasheet from that company.

    Can anyone please introduce similar companies or some parts for VDSL?



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    Re: Data Transfer over long rwisted pair cable

    Metanoia? I don't think that software solutions company actually makes products.

    Do you mean Motorola, which is now part of Arris?

    You won't find much information on the inner working of any of the Arris/Motorola products as they are all for industry use by cable companies. The modem side is designed to work with the headends of the comm companies.

    If you just what to find a VDSL chipset then I suggest you look at the following list of companies

    • Analog Devices Inc. (NYSE: ADI)
    • Broadcom Corp. (Nasdaq: BRCM)
    • Centillium Communications Inc. (Nasdaq: CTLM)
    • Conexant Systems Inc. (Nasdaq: CNXT)
    • GlobespanVirata Inc. (Nasdaq: GSPN)
    • Ikanos Communications Inc.
    • Infineon Technologies AG (NYSE/Frankfurt: IFX)
    • LSI Logic Corp. (NYSE: LSI)


    1 members found this post helpful.

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    Re: Data Transfer over long rwisted pair cable

    thanks for your helpful comment,

    look at this, it's from Metanoia
    http://www.metanoia-comm.com/admin/p...oad.php?id=101



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    Re: Data Transfer over long rwisted pair cable

    You might consider BroadR-Reach Ethernet.
    It is transmission of data using Ethernet protocol using twisted pair cable. The physical layer has been modified suitably. The speeds of 10/100/1000 Mbps is achievable as per Ethernet protocol.
    https://en.wikipedia.org/wiki/BroadR-Reach

    The PHY chips are available in the market. Everything from the Data-Link layer up to the Application layer remains the same.
    FPGA enthusiast!



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    Re: Data Transfer over long rwisted pair cable

    As far as I see, BroadR isn't suited for the intended cable length. This chip spec is referring to 15 m UTP. http://www.ieee802.org/3/1TPCESG/pub..._Spec_V3.0.pdf



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    Re: Data Transfer over long twisted pair cable

    Quote Originally Posted by std_match View Post
    1) "CAN FD" is specified for 10 meters maximum distance, the requirement here is 1500 meters. Also, the expected average bit rate is probably below 4 Mbit/s:
    https://www.computer-solutions.co.uk...n_tutorial.htm

    2)"TCP/IP" is a (software) protocol, and has nothing to do with transferring bits on the physical layer (the twisted pair).
    .
    Hello,

    I would like to relate to your opinions:

    1) It is possible (in real environment) to achieve bit rate 12 Mbit/s on "CAN FD". I agree that it is not possible for such long distance.

    2) I think it has: ADSL protocol is placed in first to layers of OSI model (it just handle sending bits over transport medium: twisted pair). In order to assure trusted comunication someone need also higer level protocols (like in OSI model):

    https://en.wikipedia.org/wiki/OSI_model

    What for to reinvent the wheel when we have efficient and proven protocol stack - TCP/IP that we can use.

    The last post in this thread described the circle and come back to such solution ;)

    Best Regards



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